<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Date
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @version    $Id: DateObject.php 16561 2009-07-08 15:05:06Z thomas $
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */

/**
 * @category   Zend
 * @package    Zend_Date
 * @subpackage Zend_Date_DateObject
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
abstract class Zend_Date_DateObject {

	/**
	 * UNIX Timestamp
	 */
	private   $_unixTimestamp;
	protected static $_cache         = null;
	protected static $_defaultOffset = 0;

	/**
	 * active timezone
	 */
	private   $_timezone    = 'UTC';
	private   $_offset      = 0;
	private   $_syncronised = 0;

	// turn off DST correction if UTC or GMT
	protected $_dst         = true;

	/**
	 * Table of Monthdays
	 */
	private static $_monthTable = array(31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31);

	/**
	 * Table of Years
	 */
	private static $_yearTable = array(
	1970 => 0,            1960 => -315619200,   1950 => -631152000,
	1940 => -946771200,   1930 => -1262304000,  1920 => -1577923200,
	1910 => -1893456000,  1900 => -2208988800,  1890 => -2524521600,
	1880 => -2840140800,  1870 => -3155673600,  1860 => -3471292800,
	1850 => -3786825600,  1840 => -4102444800,  1830 => -4417977600,
	1820 => -4733596800,  1810 => -5049129600,  1800 => -5364662400,
	1790 => -5680195200,  1780 => -5995814400,  1770 => -6311347200,
	1760 => -6626966400,  1750 => -6942499200,  1740 => -7258118400,
	1730 => -7573651200,  1720 => -7889270400,  1710 => -8204803200,
	1700 => -8520336000,  1690 => -8835868800,  1680 => -9151488000,
	1670 => -9467020800,  1660 => -9782640000,  1650 => -10098172800,
	1640 => -10413792000, 1630 => -10729324800, 1620 => -11044944000,
	1610 => -11360476800, 1600 => -11676096000);

	/**
	 * Set this object to have a new UNIX timestamp.
	 *
	 * @param  string|integer  $timestamp  OPTIONAL timestamp; defaults to local time using time()
	 * @return string|integer  old timestamp
	 * @throws Zend_Date_Exception
	 */
	protected function setUnixTimestamp($timestamp = null)
	{
		$old = $this->_unixTimestamp;

		if (is_numeric($timestamp)) {
			$this->_unixTimestamp = $timestamp;
		} else if ($timestamp === null) {
			$this->_unixTimestamp = time();
		} else {
			require_once 'Zend/Date/Exception.php';
			throw new Zend_Date_Exception('\'' . $timestamp . '\' is not a valid UNIX timestamp', $timestamp);
		}

		return $old;
	}

	/**
	 * Returns this object's UNIX timestamp
	 * A timestamp greater then the integer range will be returned as string
	 * This function does not return the timestamp as object. Use copy() instead.
	 *
	 * @return  integer|string  timestamp
	 */
	protected function getUnixTimestamp()
	{
		if ($this->_unixTimestamp === intval($this->_unixTimestamp)) {
			return (int) $this->_unixTimestamp;
		} else {
			return (string) $this->_unixTimestamp;
		}
	}

	/**
	 * Internal function.
	 * Returns time().  This method exists to allow unit tests to work-around methods that might otherwise
	 * be hard-coded to use time().  For example, this makes it possible to test isYesterday() in Date.php.
	 *
	 * @param   integer  $sync      OPTIONAL time syncronisation value
	 * @return  integer  timestamp
	 */
	protected function _getTime($sync = null)
	{
		if ($sync !== null) {
			$this->_syncronised = round($sync);
		}
		return (time() + $this->_syncronised);
	}

	/**
	 * Internal mktime function used by Zend_Date.
	 * The timestamp returned by mktime() can exceed the precision of traditional UNIX timestamps,
	 * by allowing PHP to auto-convert to using a float value.
	 *
	 * Returns a timestamp relative to 1970/01/01 00:00:00 GMT/UTC.
	 * DST (Summer/Winter) is depriciated since php 5.1.0.
	 * Year has to be 4 digits otherwise it would be recognised as
	 * year 70 AD instead of 1970 AD as expected !!
	 *
	 * @param  integer  $hour
	 * @param  integer  $minute
	 * @param  integer  $second
	 * @param  integer  $month
	 * @param  integer  $day
	 * @param  integer  $year
	 * @param  boolean  $gmt     OPTIONAL true = other arguments are for UTC time, false = arguments are for local time/date
	 * @return  integer|float  timestamp (number of seconds elapsed relative to 1970/01/01 00:00:00 GMT/UTC)
	 */
	protected function mktime($hour, $minute, $second, $month, $day, $year, $gmt = false)
	{

		// complete date but in 32bit timestamp - use PHP internal
		if ((1901 < $year) and ($year < 2038)) {

			$oldzone = @date_default_timezone_get();
			// Timezone also includes DST settings, therefor substracting the GMT offset is not enough
			// We have to set the correct timezone to get the right value
			if (($this->_timezone != $oldzone) and ($gmt === false)) {
				date_default_timezone_set($this->_timezone);
			}
			$result = ($gmt) ? @gmmktime($hour, $minute, $second, $month, $day, $year)
			:   @mktime($hour, $minute, $second, $month, $day, $year);
			date_default_timezone_set($oldzone);

			return $result;
		}

		if ($gmt !== true) {
			$second += $this->_offset;
		}

		if (isset(self::$_cache)) {
			$id = strtr('Zend_DateObject_mkTime_' . $this->_offset . '_' . $year.$month.$day.'_'.$hour.$minute.$second . '_'.(int)$gmt, '-','_');
			if ($result = self::$_cache->load($id)) {
				return unserialize($result);
			}
		}

		// date to integer
		$day   = intval($day);
		$month = intval($month);
		$year  = intval($year);

		// correct months > 12 and months < 1
		if ($month > 12) {
			$overlap = floor($month / 12);
			$year   += $overlap;
			$month  -= $overlap * 12;
		} else {
			$overlap = ceil((1 - $month) / 12);
			$year   -= $overlap;
			$month  += $overlap * 12;
		}

		$date = 0;
		if ($year >= 1970) {

			// Date is after UNIX epoch
			// go through leapyears
			// add months from latest given year
			for ($count = 1970; $count <= $year; $count++) {

				$leapyear = self::isYearLeapYear($count);
				if ($count < $year) {

					$date += 365;
					if ($leapyear === true) {
						$date++;
					}

				} else {

					for ($mcount = 0; $mcount < ($month - 1); $mcount++) {
						$date += self::$_monthTable[$mcount];
						if (($leapyear === true) and ($mcount == 1)) {
							$date++;
						}

					}
				}
			}

			$date += $day - 1;
			$date = (($date * 86400) + ($hour * 3600) + ($minute * 60) + $second);
		} else {

			// Date is before UNIX epoch
			// go through leapyears
			// add months from latest given year
			for ($count = 1969; $count >= $year; $count--) {

				$leapyear = self::isYearLeapYear($count);
				if ($count > $year)
				{
					$date += 365;
					if ($leapyear === true)
					$date++;
				} else {

					for ($mcount = 11; $mcount > ($month - 1); $mcount--) {
						$date += self::$_monthTable[$mcount];
						if (($leapyear === true) and ($mcount == 1)) {
							$date++;
						}

					}
				}
			}

			$date += (self::$_monthTable[$month - 1] - $day);
			$date = -(($date * 86400) + (86400 - (($hour * 3600) + ($minute * 60) + $second)));

			// gregorian correction for 5.Oct.1582
			if ($date < -12220185600) {
				$date += 864000;
			} else if ($date < -12219321600) {
				$date  = -12219321600;
			}
		}

		if (isset(self::$_cache)) {
			self::$_cache->save( serialize($date), $id);
		}

		return $date;
	}

	/**
	 * Returns true, if given $year is a leap year.
	 *
	 * @param  integer  $year
	 * @return boolean  true, if year is leap year
	 */
	protected static function isYearLeapYear($year)
	{
		// all leapyears can be divided through 4
		if (($year % 4) != 0) {
			return false;
		}

		// all leapyears can be divided through 400
		if ($year % 400 == 0) {
			return true;
		} else if (($year > 1582) and ($year % 100 == 0)) {
			return false;
		}

		return true;
	}

	/**
	 * Internal mktime function used by Zend_Date for handling 64bit timestamps.
	 *
	 * Returns a formatted date for a given timestamp.
	 *
	 * @param  string   $format     format for output
	 * @param  mixed    $timestamp
	 * @param  boolean  $gmt        OPTIONAL true = other arguments are for UTC time, false = arguments are for local time/date
	 * @return string
	 */
	protected function date($format, $timestamp = null, $gmt = false)
	{
		$oldzone = @date_default_timezone_get();
		if ($this->_timezone != $oldzone) {
			date_default_timezone_set($this->_timezone);
		}
		if ($timestamp === null) {
			$result = ($gmt) ? @gmdate($format) : @date($format);
			date_default_timezone_set($oldzone);
			return $result;
		}

		if (abs($timestamp) <= 0x7FFFFFFF) {
			$result = ($gmt) ? @gmdate($format, $timestamp) : @date($format, $timestamp);
			date_default_timezone_set($oldzone);
			return $result;
		}

		$jump = false;
		if (isset(self::$_cache)) {
			$idstamp = strtr('Zend_DateObject_date_' . $this->_offset . '_'. $timestamp . '_'.(int)$gmt, '-','_');
			if ($result2 = self::$_cache->load($idstamp)) {
				$timestamp = unserialize($result2);
				$jump = true;
			}
		}

		// check on false or null alone failes
		if (empty($gmt) and empty($jump)) {
			$tempstamp = $timestamp;
			if ($tempstamp > 0) {
				while (abs($tempstamp) > 0x7FFFFFFF) {
					$tempstamp -= (86400 * 23376);
				}
				$dst = date("I", $tempstamp);
				if ($dst === 1) {
					$timestamp += 3600;
				}
				$temp = date('Z', $tempstamp);
				$timestamp += $temp;
			}

			if (isset(self::$_cache)) {
				self::$_cache->save( serialize($timestamp), $idstamp);
			}
		}


		if (($timestamp < 0) and ($gmt !== true)) {
			$timestamp -= $this->_offset;
		}
		date_default_timezone_set($oldzone);

		$date = $this->getDateParts($timestamp, true);
		$length = strlen($format);
		$output = '';

		for ($i = 0; $i < $length; $i++) {

			switch($format[$i]) {

				// day formats
				case 'd':  // day of month, 2 digits, with leading zero, 01 - 31
					$output .= (($date['mday'] < 10) ? '0' . $date['mday'] : $date['mday']);
					break;

				case 'D':  // day of week, 3 letters, Mon - Sun
					$output .= date('D', 86400 * (3 + self::dayOfWeek($date['year'], $date['mon'], $date['mday'])));
					break;

				case 'j':  // day of month, without leading zero, 1 - 31
					$output .= $date['mday'];
					break;

				case 'l':  // day of week, full string name, Sunday - Saturday
					$output .= date('l', 86400 * (3 + self::dayOfWeek($date['year'], $date['mon'], $date['mday'])));
					break;

				case 'N':  // ISO 8601 numeric day of week, 1 - 7
					$day = self::dayOfWeek($date['year'], $date['mon'], $date['mday']);
					if ($day == 0) {
						$day = 7;
					}
					$output .= $day;
					break;

				case 'S':  // english suffix for day of month, st nd rd th
					if (($date['mday'] % 10) == 1) {
						$output .= 'st';
					} else if ((($date['mday'] % 10) == 2) and ($date['mday'] != 12)) {
						$output .= 'nd';
					} else if (($date['mday'] % 10) == 3) {
						$output .= 'rd';
					} else {
						$output .= 'th';
					}
					break;

				case 'w':  // numeric day of week, 0 - 6
					$output .= self::dayOfWeek($date['year'], $date['mon'], $date['mday']);
					break;

				case 'z':  // day of year, 0 - 365
					$output .= $date['yday'];
					break;


					// week formats
				case 'W':  // ISO 8601, week number of year
					$output .= $this->weekNumber($date['year'], $date['mon'], $date['mday']);
					break;


					// month formats
				case 'F':  // string month name, january - december
					$output .= date('F', mktime(0, 0, 0, $date['mon'], 2, 1971));
					break;

				case 'm':  // number of month, with leading zeros, 01 - 12
					$output .= (($date['mon'] < 10) ? '0' . $date['mon'] : $date['mon']);
					break;

				case 'M':  // 3 letter month name, Jan - Dec
					$output .= date('M',mktime(0, 0, 0, $date['mon'], 2, 1971));
					break;

				case 'n':  // number of month, without leading zeros, 1 - 12
					$output .= $date['mon'];
					break;

				case 't':  // number of day in month
					$output .= self::$_monthTable[$date['mon'] - 1];
					break;


					// year formats
				case 'L':  // is leap year ?
					$output .= (self::isYearLeapYear($date['year'])) ? '1' : '0';
					break;

				case 'o':  // ISO 8601 year number
					$week = $this->weekNumber($date['year'], $date['mon'], $date['mday']);
					if (($week > 50) and ($date['mon'] == 1)) {
						$output .= ($date['year'] - 1);
					} else {
						$output .= $date['year'];
					}
					break;

				case 'Y':  // year number, 4 digits
					$output .= $date['year'];
					break;

				case 'y':  // year number, 2 digits
					$output .= substr($date['year'], strlen($date['year']) - 2, 2);
					break;


					// time formats
				case 'a':  // lower case am/pm
					$output .= (($date['hours'] >= 12) ? 'pm' : 'am');
					break;

				case 'A':  // upper case am/pm
					$output .= (($date['hours'] >= 12) ? 'PM' : 'AM');
					break;

				case 'B':  // swatch internet time
					$dayseconds = ($date['hours'] * 3600) + ($date['minutes'] * 60) + $date['seconds'];
					if ($gmt === true) {
						$dayseconds += 3600;
					}
					$output .= (int) (($dayseconds % 86400) / 86.4);
					break;

				case 'g':  // hours without leading zeros, 12h format
					if ($date['hours'] > 12) {
						$hour = $date['hours'] - 12;
					} else {
						if ($date['hours'] == 0) {
							$hour = '12';
						} else {
							$hour = $date['hours'];
						}
					}
					$output .= $hour;
					break;

				case 'G':  // hours without leading zeros, 24h format
					$output .= $date['hours'];
					break;

				case 'h':  // hours with leading zeros, 12h format
					if ($date['hours'] > 12) {
						$hour = $date['hours'] - 12;
					} else {
						if ($date['hours'] == 0) {
							$hour = '12';
						} else {
							$hour = $date['hours'];
						}
					}
					$output .= (($hour < 10) ? '0'.$hour : $hour);
					break;

				case 'H':  // hours with leading zeros, 24h format
					$output .= (($date['hours'] < 10) ? '0' . $date['hours'] : $date['hours']);
					break;

				case 'i':  // minutes with leading zeros
					$output .= (($date['minutes'] < 10) ? '0' . $date['minutes'] : $date['minutes']);
					break;

				case 's':  // seconds with leading zeros
					$output .= (($date['seconds'] < 10) ? '0' . $date['seconds'] : $date['seconds']);
					break;


					// timezone formats
				case 'e':  // timezone identifier
					if ($gmt === true) {
						$output .= gmdate('e', mktime($date['hours'], $date['minutes'], $date['seconds'],
						$date['mon'], $date['mday'], 2000));
					} else {
						$output .=   date('e', mktime($date['hours'], $date['minutes'], $date['seconds'],
						$date['mon'], $date['mday'], 2000));
					}
					break;

				case 'I':  // daylight saving time or not
					if ($gmt === true) {
						$output .= gmdate('I', mktime($date['hours'], $date['minutes'], $date['seconds'],
						$date['mon'], $date['mday'], 2000));
					} else {
						$output .=   date('I', mktime($date['hours'], $date['minutes'], $date['seconds'],
						$date['mon'], $date['mday'], 2000));
					}
					break;

				case 'O':  // difference to GMT in hours
					$gmtstr = ($gmt === true) ? 0 : $this->getGmtOffset();
					$output .= sprintf('%s%04d', ($gmtstr <= 0) ? '+' : '-', abs($gmtstr) / 36);
					break;

				case 'P':  // difference to GMT with colon
					$gmtstr = ($gmt === true) ? 0 : $this->getGmtOffset();
					$gmtstr = sprintf('%s%04d', ($gmtstr <= 0) ? '+' : '-', abs($gmtstr) / 36);
					$output = $output . substr($gmtstr, 0, 3) . ':' . substr($gmtstr, 3);
					break;

				case 'T':  // timezone settings
					if ($gmt === true) {
						$output .= gmdate('T', mktime($date['hours'], $date['minutes'], $date['seconds'],
						$date['mon'], $date['mday'], 2000));
					} else {
						$output .=   date('T', mktime($date['hours'], $date['minutes'], $date['seconds'],
						$date['mon'], $date['mday'], 2000));
					}
					break;

				case 'Z':  // timezone offset in seconds
					$output .= ($gmt === true) ? 0 : -$this->getGmtOffset();
					break;


					// complete time formats
				case 'c':  // ISO 8601 date format
					$difference = $this->getGmtOffset();
					$difference = sprintf('%s%04d', ($difference <= 0) ? '+' : '-', abs($difference) / 36);
					$output .= $date['year'] . '-'
					. (($date['mon']     < 10) ? '0' . $date['mon']     : $date['mon'])     . '-'
					. (($date['mday']    < 10) ? '0' . $date['mday']    : $date['mday'])    . 'T'
					. (($date['hours']   < 10) ? '0' . $date['hours']   : $date['hours'])   . ':'
					. (($date['minutes'] < 10) ? '0' . $date['minutes'] : $date['minutes']) . ':'
					. (($date['seconds'] < 10) ? '0' . $date['seconds'] : $date['seconds'])
					. $difference;
					break;

				case 'r':  // RFC 2822 date format
					$difference = $this->getGmtOffset();
					$difference = sprintf('%s%04d', ($difference <= 0) ? '+' : '-', abs($difference) / 36);
					$output .= gmdate('D', 86400 * (3 + self::dayOfWeek($date['year'], $date['mon'], $date['mday']))) . ', '
					. (($date['mday']    < 10) ? '0' . $date['mday']    : $date['mday'])    . ' '
					. date('M', mktime(0, 0, 0, $date['mon'], 2, 1971)) . ' '
					. $date['year'] . ' '
					. (($date['hours']   < 10) ? '0' . $date['hours']   : $date['hours'])   . ':'
					. (($date['minutes'] < 10) ? '0' . $date['minutes'] : $date['minutes']) . ':'
					. (($date['seconds'] < 10) ? '0' . $date['seconds'] : $date['seconds']) . ' '
					. $difference;
					break;

				case 'U':  // Unix timestamp
					$output .= $timestamp;
					break;


					// special formats
				case "\\":  // next letter to print with no format
					$i++;
					if ($i < $length) {
						$output .= $format[$i];
					}
					break;

				default:  // letter is no format so add it direct
					$output .= $format[$i];
					break;
			}
		}

		return (string) $output;
	}

	/**
	 * Returns the day of week for a Gregorian calendar date.
	 * 0 = sunday, 6 = saturday
	 *
	 * @param  integer  $year
	 * @param  integer  $month
	 * @param  integer  $day
	 * @return integer  dayOfWeek
	 */
	protected static function dayOfWeek($year, $month, $day)
	{
		if ((1901 < $year) and ($year < 2038)) {
			return (int) date('w', mktime(0, 0, 0, $month, $day, $year));
		}

		// gregorian correction
		$correction = 0;
		if (($year < 1582) or (($year == 1582) and (($month < 10) or (($month == 10) && ($day < 15))))) {
			$correction = 3;
		}

		if ($month > 2) {
			$month -= 2;
		} else {
			$month += 10;
			$year--;
		}

		$day  = floor((13 * $month - 1) / 5) + $day + ($year % 100) + floor(($year % 100) / 4);
		$day += floor(($year / 100) / 4) - 2 * floor($year / 100) + 77 + $correction;

		return (int) ($day - 7 * floor($day / 7));
	}

	/**
	 * Internal getDateParts function for handling 64bit timestamps, similar to:
	 * http://www.php.net/getdate
	 *
	 * Returns an array of date parts for $timestamp, relative to 1970/01/01 00:00:00 GMT/UTC.
	 *
	 * $fast specifies ALL date parts should be returned (slower)
	 * Default is false, and excludes $dayofweek, weekday, month and timestamp from parts returned.
	 *
	 * @param   mixed    $timestamp
	 * @param   boolean  $fast   OPTIONAL defaults to fast (false), resulting in fewer date parts
	 * @return  array
	 */
	protected function getDateParts($timestamp = null, $fast = null)
	{

		// actual timestamp
		if (!is_numeric($timestamp)) {
			return getdate();
		}

		// 32bit timestamp
		if (abs($timestamp) <= 0x7FFFFFFF) {
			return @getdate((int) $timestamp);
		}

		if (isset(self::$_cache)) {
			$id = strtr('Zend_DateObject_getDateParts_' . $timestamp.'_'.(int)$fast, '-','_');
			if ($result = self::$_cache->load($id)) {
				return unserialize($result);
			}
		}

		$otimestamp = $timestamp;
		$numday = 0;
		$month = 0;
		// gregorian correction
		if ($timestamp < -12219321600) {
			$timestamp -= 864000;
		}

		// timestamp lower 0
		if ($timestamp < 0) {
			$sec = 0;
			$act = 1970;

			// iterate through 10 years table, increasing speed
			foreach(self::$_yearTable as $year => $seconds) {
				if ($timestamp >= $seconds) {
					$i = $act;
					break;
				}
				$sec = $seconds;
				$act = $year;
			}

			$timestamp -= $sec;
			if (!isset($i)) {
				$i = $act;
			}

			// iterate the max last 10 years
			do {
				--$i;
				$day = $timestamp;

				$timestamp += 31536000;
				$leapyear = self::isYearLeapYear($i);
				if ($leapyear === true) {
					$timestamp += 86400;
				}

				if ($timestamp >= 0) {
					$year = $i;
					break;
				}
			} while ($timestamp < 0);

			$secondsPerYear = 86400 * ($leapyear ? 366 : 365) + $day;

			$timestamp = $day;
			// iterate through months
			for ($i = 12; --$i >= 0;) {
				$day = $timestamp;

				$timestamp += self::$_monthTable[$i] * 86400;
				if (($leapyear === true) and ($i == 1)) {
					$timestamp += 86400;
				}

				if ($timestamp >= 0) {
					$month  = $i;
					$numday = self::$_monthTable[$i];
					if (($leapyear === true) and ($i == 1)) {
						++$numday;
					}
					break;
				}
			}

			$timestamp  = $day;
			$numberdays = $numday + ceil(($timestamp + 1) / 86400);

			$timestamp += ($numday - $numberdays + 1) * 86400;
			$hours      = floor($timestamp / 3600);
		} else {

			// iterate through years
			for ($i = 1970;;$i++) {
				$day = $timestamp;

				$timestamp -= 31536000;
				$leapyear = self::isYearLeapYear($i);
				if ($leapyear === true) {
					$timestamp -= 86400;
				}

				if ($timestamp < 0) {
					$year = $i;
					break;
				}
			}

			$secondsPerYear = $day;

			$timestamp = $day;
			// iterate through months
			for ($i = 0; $i <= 11; $i++) {
				$day = $timestamp;
				$timestamp -= self::$_monthTable[$i] * 86400;

				if (($leapyear === true) and ($i == 1)) {
					$timestamp -= 86400;
				}

				if ($timestamp < 0) {
					$month  = $i;
					$numday = self::$_monthTable[$i];
					if (($leapyear === true) and ($i == 1)) {
						++$numday;
					}
					break;
				}
			}

			$timestamp  = $day;
			$numberdays = ceil(($timestamp + 1) / 86400);
			$timestamp  = $timestamp - ($numberdays - 1) * 86400;
			$hours = floor($timestamp / 3600);
		}

		$timestamp -= $hours * 3600;

		$month  += 1;
		$minutes = floor($timestamp / 60);
		$seconds = $timestamp - $minutes * 60;

		if ($fast === true) {
			$array = array(
                'seconds' => $seconds,
                'minutes' => $minutes,
                'hours'   => $hours,
                'mday'    => $numberdays,
                'mon'     => $month,
                'year'    => $year,
                'yday'    => floor($secondsPerYear / 86400),
			);
		} else {

			$dayofweek = self::dayOfWeek($year, $month, $numberdays);
			$array = array(
                    'seconds' => $seconds,
                    'minutes' => $minutes,
                    'hours'   => $hours,
                    'mday'    => $numberdays,
                    'wday'    => $dayofweek,
                    'mon'     => $month,
                    'year'    => $year,
                    'yday'    => floor($secondsPerYear / 86400),
                    'weekday' => gmdate('l', 86400 * (3 + $dayofweek)),
                    'month'   => gmdate('F', mktime(0, 0, 0, $month, 1, 1971)),
			0         => $otimestamp
			);
		}

		if (isset(self::$_cache)) {
			self::$_cache->save( serialize($array), $id);
		}

		return $array;
	}

	/**
	 * Internal getWeekNumber function for handling 64bit timestamps
	 *
	 * Returns the ISO 8601 week number of a given date
	 *
	 * @param  integer  $year
	 * @param  integer  $month
	 * @param  integer  $day
	 * @return integer
	 */
	protected function weekNumber($year, $month, $day)
	{
		if ((1901 < $year) and ($year < 2038)) {
			return (int) date('W', mktime(0, 0, 0, $month, $day, $year));
		}

		$dayofweek = self::dayOfWeek($year, $month, $day);
		$firstday  = self::dayOfWeek($year, 1, 1);
		if (($month == 1) and (($firstday < 1) or ($firstday > 4)) and ($day < 4)) {
			$firstday  = self::dayOfWeek($year - 1, 1, 1);
			$month     = 12;
			$day       = 31;

		} else if (($month == 12) and ((self::dayOfWeek($year + 1, 1, 1) < 5) and
		(self::dayOfWeek($year + 1, 1, 1) > 0))) {
			return 1;
		}

		return intval (((self::dayOfWeek($year, 1, 1) < 5) and (self::dayOfWeek($year, 1, 1) > 0)) +
		4 * ($month - 1) + (2 * ($month - 1) + ($day - 1) + $firstday - $dayofweek + 6) * 36 / 256);
	}

	/**
	 * Internal _range function
	 * Sets the value $a to be in the range of [0, $b]
	 *
	 * @param float $a - value to correct
	 * @param float $b - maximum range to set
	 */
	private function _range($a, $b) {
		while ($a < 0) {
			$a += $b;
		}
		while ($a >= $b) {
			$a -= $b;
		}
		return $a;
	}

	/**
	 * Calculates the sunrise or sunset based on a location
	 *
	 * @param  array  $location  Location for calculation MUST include 'latitude', 'longitude', 'horizon'
	 * @param  bool   $horizon   true: sunrise; false: sunset
	 * @return mixed  - false: midnight sun, integer:
	 */
	protected function calcSun($location, $horizon, $rise = false)
	{
		// timestamp within 32bit
		if (abs($this->_unixTimestamp) <= 0x7FFFFFFF) {
			if ($rise === false) {
				return date_sunset($this->_unixTimestamp, SUNFUNCS_RET_TIMESTAMP, $location['latitude'],
				$location['longitude'], 90 + $horizon, $this->getGmtOffset() / 3600);
			}
			return date_sunrise($this->_unixTimestamp, SUNFUNCS_RET_TIMESTAMP, $location['latitude'],
			$location['longitude'], 90 + $horizon, $this->getGmtOffset() / 3600);
		}

		// self calculation - timestamp bigger than 32bit
		// fix circle values
		$quarterCircle      = 0.5 * M_PI;
		$halfCircle         =       M_PI;
		$threeQuarterCircle = 1.5 * M_PI;
		$fullCircle         = 2   * M_PI;

		// radiant conversion for coordinates
		$radLatitude  = $location['latitude']   * $halfCircle / 180;
		$radLongitude = $location['longitude']  * $halfCircle / 180;

		// get solar coordinates
		$tmpRise       = $rise ? $quarterCircle : $threeQuarterCircle;
		$radDay        = $this->date('z',$this->_unixTimestamp) + ($tmpRise - $radLongitude) / $fullCircle;

		// solar anomoly and longitude
		$solAnomoly    = $radDay * 0.017202 - 0.0574039;
		$solLongitude  = $solAnomoly + 0.0334405 * sin($solAnomoly);
		$solLongitude += 4.93289 + 3.49066E-4 * sin(2 * $solAnomoly);

		// get quadrant
		$solLongitude = $this->_range($solLongitude, $fullCircle);

		if (($solLongitude / $quarterCircle) - intval($solLongitude / $quarterCircle) == 0) {
			$solLongitude += 4.84814E-6;
		}

		// solar ascension
		$solAscension = sin($solLongitude) / cos($solLongitude);
		$solAscension = atan2(0.91746 * $solAscension, 1);

		// adjust quadrant
		if ($solLongitude > $threeQuarterCircle) {
			$solAscension += $fullCircle;
		} else if ($solLongitude > $quarterCircle) {
			$solAscension += $halfCircle;
		}

		// solar declination
		$solDeclination  = 0.39782 * sin($solLongitude);
		$solDeclination /=  sqrt(-$solDeclination * $solDeclination + 1);
		$solDeclination  = atan2($solDeclination, 1);

		$solHorizon = $horizon - sin($solDeclination) * sin($radLatitude);
		$solHorizon /= cos($solDeclination) * cos($radLatitude);

		// midnight sun, always night
		if (abs($solHorizon) > 1) {
			return false;
		}

		$solHorizon /= sqrt(-$solHorizon * $solHorizon + 1);
		$solHorizon  = $quarterCircle - atan2($solHorizon, 1);

		if ($rise) {
			$solHorizon = $fullCircle - $solHorizon;
		}

		// time calculation
		$localTime     = $solHorizon + $solAscension - 0.0172028 * $radDay - 1.73364;
		$universalTime = $localTime - $radLongitude;

		// determinate quadrant
		$universalTime = $this->_range($universalTime, $fullCircle);

		// radiant to hours
		$universalTime *= 24 / $fullCircle;

		// convert to time
		$hour = intval($universalTime);
		$universalTime    = ($universalTime - $hour) * 60;
		$min  = intval($universalTime);
		$universalTime    = ($universalTime - $min) * 60;
		$sec  = intval($universalTime);

		return $this->mktime($hour, $min, $sec, $this->date('m', $this->_unixTimestamp),
		$this->date('j', $this->_unixTimestamp), $this->date('Y', $this->_unixTimestamp),
		-1, true);
	}

	/**
	 * Sets a new timezone for calculation of $this object's gmt offset.
	 * For a list of supported timezones look here: http://php.net/timezones
	 * If no timezone can be detected or the given timezone is wrong UTC will be set.
	 *
	 * @param  string  $zone      OPTIONAL timezone for date calculation; defaults to date_default_timezone_get()
	 * @return Zend_Date_DateObject Provides fluent interface
	 * @throws Zend_Date_Exception
	 */
	public function setTimezone($zone = null)
	{
		$oldzone = @date_default_timezone_get();
		if ($zone === null) {
			$zone = $oldzone;
		}

		// throw an error on false input, but only if the new date extension is available
		if (function_exists('timezone_open')) {
			if (!@timezone_open($zone)) {
				require_once 'Zend/Date/Exception.php';
				throw new Zend_Date_Exception("timezone ($zone) is not a known timezone", $zone);
			}
		}
		// this can generate an error if the date extension is not available and a false timezone is given
		$result = @date_default_timezone_set($zone);
		if ($result === true) {
			$this->_offset   = mktime(0, 0, 0, 1, 2, 1970) - gmmktime(0, 0, 0, 1, 2, 1970);
			$this->_timezone = $zone;
		}
		date_default_timezone_set($oldzone);

		if (($zone == 'UTC') or ($zone == 'GMT')) {
			$this->_dst = false;
		} else {
			$this->_dst = true;
		}

		return $this;
	}

	/**
	 * Return the timezone of $this object.
	 * The timezone is initially set when the object is instantiated.
	 *
	 * @return  string  actual set timezone string
	 */
	public function getTimezone()
	{
		return $this->_timezone;
	}

	/**
	 * Return the offset to GMT of $this object's timezone.
	 * The offset to GMT is initially set when the object is instantiated using the currently,
	 * in effect, default timezone for PHP functions.
	 *
	 * @return  integer  seconds difference between GMT timezone and timezone when object was instantiated
	 */
	public function getGmtOffset()
	{
		$date   = $this->getDateParts($this->getUnixTimestamp(), true);
		$zone   = @date_default_timezone_get();
		$result = @date_default_timezone_set($this->_timezone);
		if ($result === true) {
			$offset = $this->mktime($date['hours'], $date['minutes'], $date['seconds'],
			$date['mon'], $date['mday'], $date['year'], false)
			- $this->mktime($date['hours'], $date['minutes'], $date['seconds'],
			$date['mon'], $date['mday'], $date['year'], true);
		}
		date_default_timezone_set($zone);

		return $offset;
	}
}
